EP0464386A1 - Gas spring - Google Patents
Gas spring Download PDFInfo
- Publication number
- EP0464386A1 EP0464386A1 EP91109215A EP91109215A EP0464386A1 EP 0464386 A1 EP0464386 A1 EP 0464386A1 EP 91109215 A EP91109215 A EP 91109215A EP 91109215 A EP91109215 A EP 91109215A EP 0464386 A1 EP0464386 A1 EP 0464386A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- housing
- rod
- seal
- gas
- spring device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
- F16F9/32—Details
- F16F9/36—Special sealings, including sealings or guides for piston-rods
- F16F9/362—Combination of sealing and guide arrangements for piston rods
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
- F16F9/02—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium using gas only or vacuum
- F16F9/0209—Telescopic
Definitions
- This invention relates to pneumatic devices, and more particularly to gas springs.
- Gas springs are utilized typically to yieldingly resist movement of a body such as a clamping ring for a metal blank in a die in a press for forming sheet metal parts.
- Gas springs are generally constructed with an actuating rod connected to a piston or head slidably received in a cylinder having a chamber which is charged at a predetermined pressure, such as 13,79 MPa (2000 PSI), with an inert gas, such as nitrogen.
- a predetermined pressure such as 13,79 MPa (2000 PSI)
- an inert gas such as nitrogen.
- This provides a gas spring or cushion permitting the rod to yieldably move toward its retracted position when a force applied externally to the rod exceeds the force produced thereon by the gas in the chamber.
- the gas therein is compressed to a maximum operating pressure which is usually in the range of about 20,69 MPa to 34,48 MPa (3000 to 5000 PSI), depending on the volume of the chamber and the effective area and stroke of the rod and piston.
- the pressure to which a self-contained gas spring is initially charged is not varied or changed.
- the spring is initially charged, relieved and recharged through a high pressure valve of the type commonly used in aircraft struts and
- gas springs have been constructed with the rod being slidably received in a bearing and seal housing assembly received in the cylinder.
- This housing assembly has a rear housing slidably received on a front housing with a rod gasket or seal therebetween.
- the seal is compressed axially so that it expands radially inward into firm sealing engagement with the rod by the force produced by pressurized gas in the chamber acting on the rear housing.
- the movement of the housing causes wear on adjacent parts and wear of the housing itself.
- Such a gas spring is shown in U.S. Patent No. 4,792,128, which has a positive stop preventing the head from striking the housing assembly and damaging the bearings and seals.
- U.S. Patent No. 4,838,527 shows a gas spring which can be operated with either an external source of gas or as a precharged and self-contained unit by changing first and second valves assemblies either of which can be installed in the same cavity in the cylinder.
- a gas spring which provides two stages of resistance to axial movement, by a first head and rod slidably disposed within a second rod with a head, with both of the heads subjected to pressurized gas in a common chamber within the cylinder.
- a seal for each rod provides sealing engagement when the force of pressurized gas acts upon the seal.
- the seal provides sealing engagement without being axially compressed and radially expanded.
- the seal may be used in single stage and two stage gas springs.
- a positive stop for each rod is provided, preferably as a part of the housing for its bearings and seal.
- the seal is a flexible annular sealing element which when viewed in cross section is generally a C-shape, with arms constructed and arranged so that the free edges of the seal are biased into sealing engagement by pressurized gas acting on the arms.
- each arm has a terminal portion with a lip, biased inward in a relaxed state. Pressurized gas acts on the lip to force it outward and extend it to provide additional sealing surface area and a relatively sharp edge in contact with an adjacent surface to provide improved sealing.
- Objects features and advantages of this invention are to provide a gas spring device which will provide a substantially lesser force at the beginning of its stroke in relation to the force at the end of its stroke, significantly decreases the tendency to slow down or stall a press, improved rod sealing characteristics, improved in service useful life, and is rugged, durable, reliable, of relatively simple design and economical manufacture and assembly.
- Fig. 1 illustrates a two-stage gas spring 10 embodying this invention.
- This gas spring 10 has a cylinder 12 defining at least in part a gas chamber 14 in which first and second rods 16 and 18 are telescopically received.
- the rods 16, 18 are yieldably urged to their extended positions by pressurized gas in the chamber 14 which acts on the pistons or heads 20, 22 of the rods 16, 18.
- a force is applied externally to the rods 16, 18, such as through a die plate, which force is greater than the force produced on the rod or rods by the gas in the chamber, initially the first rod 16 and then subsequently both rods 16, 18 in unison are yieldably moved toward their retracted positions.
- the cylinder 12 has a separate tube 24 and an end cap 26 permanently fixed to the tube by a circumferentially continuous seam weld.
- a filler and bleed poppet valve assembly 28 is preferably removably received in a valve cavity 30 in the cap 26 and communicates with the chamber 14 through a passage 32.
- the first rod 16 is slidably received in a bearing and seal assembly 34 disposed in a bore 36 through the second rod 18 and releasably retained therein by ring segments 38 received in a groove 40 in the bore 36.
- This assembly has a front housing 42 slidably received preferably with an interference fit in a rear housing 44 with a rod seal 46 received between them in a counterbore 48 in the rear housing 44.
- a seal is provided between the second rod 18 and the rear housing 44 by an O-ring 52 and back-up ring 53 received in a groove 54 therein.
- the rod 16 is slidably received in bearings 56, 57 received in counterbores 58 in the front and rear housings 42, 44.
- a rod scraper 60 encircles the rod 16 and is received in a recess 62 in the front housing 42, and a dust cap 64 overlies the assembly 34 and is received and frictionally retained in the end 66 of the second rod 18.
- the second rod 18 is slidably received in a bearing and seal assembly 68 disposed in the tube 24 of the cylinder 12 and releasably retained therein by ring segments 70 received in a groove 72 in the tube 24.
- This assembly has a front housing 74 slidably received preferably with an interference fit in a rear housing 76 with a rod seal 77 received between them in a counterbore 78 in the rear housing 76.
- a seal between the tube 24 and the rear housing 76 is provided by an O-ring 80 and back-up ring 81 received in a groove 82 therein.
- the second rod 18 is slidably received in bearings 84, 85 which are received in counterbores 86 in the front and rear housings 74, 76.
- a rod scraper 89 is received in a recess 90 in the front housing 74 and a dust cap 92 overlies the bearing assembly 68 and is received and frictionally retained in the end 94 of the tube 24.
- the bearings 58, 84 are of a suitable material such as sintered bronze. To insure adequate lubrication of the bearings 56, 57, 84, 85, and particularly the rear bearings, they are impregnated with lubricant and a small quantity of a synthetic high temperature lubricating oil is also disposed in the chamber 14.
- each rod 16, 18 and its bearings 58, 84 relatively little clearance is provided between each rod 16, 18 and its bearings 58, 84.
- This clearance is usually about 0.002 to 0.004 of an inch per side or a total clearance of 0.004 to 0.008 of an inch between the diameters of each rod and its associated bearings.
- the bearings are sized after being pressed into their housings.
- Movement of the first rod 16 to its extended position is limited by a positive stop 96 provided by cooperation of an end face 98 of the rear housing 44 with a complementary shoulder 100 on the head 20 of the first rod 16. Movement of the second rod 18 to its extended position is limited by a positive stop 102 provided by engagement of a conical surface 104 on the back face 106 of the rear housing 76 with a complementary surface on the head 22 of the second rod 18.
- these seals have a circumferentially continuous sealing ring 110 which, as shown in Fig. 2, in a relaxed or unflexed state, has in cross section a generally C-shape with side walls or arms 112, the central portions of which are urged into contact with their adjacent rod and housing surfaces by a circumferentially continuous metal spring element 114 received in the ring 110.
- the ring 110 is made of a low friction and highly wear resistant elastomeric material such as an ultra high molecular weight polyethylene.
- the free edges of the arms 112 have generally right angular surfaces defining a sharp peripheral edge or lip 116.
- the arms 112 are extended and forced along with the lips 116 into firm sealing engagement with the adjacent surfaces of the rods 16, 18 and housings 44, 76.
- the pressurized gas forces the ring 110 to engage with and conform to the peripheral surfaces of the cavity in which it is received.
- Appropriate seals as thus far described are disclosed in U.S. Patent 4,508,356 and commercially available from Tetraflour, Inc., 2051 E. Maple Avenue, EI Segundo, California 90245, under the tradename "TETRALENE MULTI-FLEX SEALS".
- the outer wall or arm 118 of the ring 110 is substantially thicker than its inner wall or arm 120.
- the radial thickness of the outer wall 118 is about 110% to 250% times the radial thickness of the inner wall 120.
- each seal continuously communicates with the chamber 14 through one or more passages 124, which are preferably formed by interconnected grooves 126 in the rear bearings 56, 84.
- grooves 126 extend radially across the opposed end faces 128 of each rear bearing 56, 84 and are interconnected by a groove 126 extending axially across the outer peripheral surface 130 of each bearing 56, 84.
- these passages 124 also substantially equalize the pressure of gas acting on the opposed end faces 128 of each bearing 56, 84.
- This bearing, seal and housing construction permits and facilitates the use of close tolerances and even interference fits between the bearings and housing members.
- the housing member is not required to move axially to compress and radially expand the seal. Elimination of this movement and use of close tolerances substantially reduces wear on the component parts and greatly extends the useful service life of the gas spring. Moreover, these close tolerances in conjunction with lubrication of the parts further enhances sealing and minimizes leakage of pressurized gas from the chamber.
- the chamber is precharged with a compressed gas, such as nitrogen, to a relatively high internal pressure such as 13,79 MPa (2000 PSI).
- a relatively small force is required to initially retract the first rod 16 and this force increases only modestly as the first rod 16 is retracted, such as by advancement of the die plate, until the plate also bears on the second rod 18.
- This relatively low force for displacement of the first rod 16 is due to the relatively small area of its head 20 and the fact that the movement of the first rod 16 and head 20 only moderately compresses the gas in the chamber 14 and thereby only moderately increases the force required to continue to move the rod 16 toward its retracted position.
- Fig. 5 illustrates a modified gas spring 134 which is the same as the two-stage gas spring 10 except that is has a single rod 136 with a seal 138.
- This spring 134 illustrates application of the seal, bearing housing assembly 140 to gas springs having a single rod 136 and head 142.
- both rods were moved simultaneously and additional 2,54 cm (1 ") by application of a force to their free ends which increased linearly from about 27,17 kN to 43,67 kN (6108 lbs. to 9816 lbs. ).
- the rod moved towards its retracted position from 0 to 10,16 cm (0 to 4") by application of a force to its free end which increased generally linearly from 27,17 kN to 43,23 kN (6108 lbs. to 9719 Ibs. ).
Abstract
Description
- This invention relates to pneumatic devices, and more particularly to gas springs.
- Gas springs are utilized typically to yieldingly resist movement of a body such as a clamping ring for a metal blank in a die in a press for forming sheet metal parts.
- Gas springs are generally constructed with an actuating rod connected to a piston or head slidably received in a cylinder having a chamber which is charged at a predetermined pressure, such as 13,79 MPa (2000 PSI), with an inert gas, such as nitrogen. This provides a gas spring or cushion permitting the rod to yieldably move toward its retracted position when a force applied externally to the rod exceeds the force produced thereon by the gas in the chamber. When the rod and head are forced into the chamber, the gas therein is compressed to a maximum operating pressure which is usually in the range of about 20,69 MPa to 34,48 MPa (3000 to 5000 PSI), depending on the volume of the chamber and the effective area and stroke of the rod and piston. In normal use, the pressure to which a self-contained gas spring is initially charged is not varied or changed. The spring is initially charged, relieved and recharged through a high pressure valve of the type commonly used in aircraft struts and accumulators.
- Previously, gas springs have been constructed with the rod being slidably received in a bearing and seal housing assembly received in the cylinder. This housing assembly has a rear housing slidably received on a front housing with a rod gasket or seal therebetween. In use, the seal is compressed axially so that it expands radially inward into firm sealing engagement with the rod by the force produced by pressurized gas in the chamber acting on the rear housing. The movement of the housing causes wear on adjacent parts and wear of the housing itself. Such a gas spring is shown in U.S. Patent No. 4,792,128, which has a positive stop preventing the head from striking the housing assembly and damaging the bearings and seals.
- U.S. Patent No. 4,838,527 shows a gas spring which can be operated with either an external source of gas or as a precharged and self-contained unit by changing first and second valves assemblies either of which can be installed in the same cavity in the cylinder.
- These gas springs require a substantial force to begin moving their rods toward their retracted positions. This force increases rapidly as their rods are retracted. The force required to begin this retraction stroke is often so substantial that a mechanical crankshaft type press may have difficulty producing sufficient force to retract the rod. This lengthens the press cycle time or even stalls the press. This may occur because the press produces relatively little force at the beginning of its stroke and most of its force near the very end of its stroke. With conventional presses and dies relatively little force need be applied to the clamping ring during the initial portion of the press stroke and a much greater force is required near the end of the press stroke. Excessive forces cause excessive wear on the crank, crank bearings and die parts. Thus, the desired force curve for press operations is opposite to that produced by prior gas springs.
- A gas spring which provides two stages of resistance to axial movement, by a first head and rod slidably disposed within a second rod with a head, with both of the heads subjected to pressurized gas in a common chamber within the cylinder. Preferably, a seal for each rod provides sealing engagement when the force of pressurized gas acts upon the seal. Hence, the seal provides sealing engagement without being axially compressed and radially expanded. The seal may be used in single stage and two stage gas springs. Desirably, a positive stop for each rod is provided, preferably as a part of the housing for its bearings and seal.
- Preferably, the seal is a flexible annular sealing element which when viewed in cross section is generally a C-shape, with arms constructed and arranged so that the free edges of the seal are biased into sealing engagement by pressurized gas acting on the arms. Preferably, each arm has a terminal portion with a lip, biased inward in a relaxed state. Pressurized gas acts on the lip to force it outward and extend it to provide additional sealing surface area and a relatively sharp edge in contact with an adjacent surface to provide improved sealing.
- Objects features and advantages of this invention are to provide a gas spring device which will provide a substantially lesser force at the beginning of its stroke in relation to the force at the end of its stroke, significantly decreases the tendency to slow down or stall a press, improved rod sealing characteristics, improved in service useful life, and is rugged, durable, reliable, of relatively simple design and economical manufacture and assembly.
- These and other objects, features and advantages of this invention will be apparent from the following detailed description, appended claims and accompanying drawings in which:
- Fig. 1 is a sectional view of a two stage gas spring embodying this invention.
- Fig. 2 is an enlarged view of the encircled portion of Fig. 1 showing a seal in its relaxed state.
- Fig. 3 is an enlarged view of the encircled portion of Fig. 1 showing a seal in its extended state.
- Fig. 4 is a force vs. displacement curve of the two stage gas spring.
- Fig. 5 is a sectional view of a single stage gas spring embodying this invention.
- Fig. 1 illustrates a two-
stage gas spring 10 embodying this invention. Thisgas spring 10 has acylinder 12 defining at least in part agas chamber 14 in which first andsecond rods rods chamber 14 which acts on the pistons orheads 20, 22 of therods rods first rod 16 and then subsequently bothrods - Preferably, the
cylinder 12 has aseparate tube 24 and anend cap 26 permanently fixed to the tube by a circumferentially continuous seam weld. A filler and bleedpoppet valve assembly 28 is preferably removably received in avalve cavity 30 in thecap 26 and communicates with thechamber 14 through apassage 32. - The
first rod 16 is slidably received in a bearing andseal assembly 34 disposed in abore 36 through thesecond rod 18 and releasably retained therein byring segments 38 received in agroove 40 in thebore 36. This assembly has afront housing 42 slidably received preferably with an interference fit in arear housing 44 with arod seal 46 received between them in acounterbore 48 in therear housing 44. A seal is provided between thesecond rod 18 and therear housing 44 by an O-ring 52 and back-up ring 53 received in a groove 54 therein. Therod 16 is slidably received in bearings 56, 57 received in counterbores 58 in the front andrear housings assembly 34, preferably a rod scraper 60 encircles therod 16 and is received in a recess 62 in thefront housing 42, and adust cap 64 overlies theassembly 34 and is received and frictionally retained in theend 66 of thesecond rod 18. - Similarly, the
second rod 18 is slidably received in a bearing andseal assembly 68 disposed in thetube 24 of thecylinder 12 and releasably retained therein byring segments 70 received in agroove 72 in thetube 24. This assembly has afront housing 74 slidably received preferably with an interference fit in arear housing 76 with arod seal 77 received between them in acounterbore 78 in therear housing 76. A seal between thetube 24 and therear housing 76 is provided by an O-ring 80 and back-up ring 81 received in a groove 82 therein. Thesecond rod 18 is slidably received in bearings 84, 85 which are received in counterbores 86 in the front andrear housings assembly 68, a rod scraper 89 is received in a recess 90 in thefront housing 74 and adust cap 92 overlies thebearing assembly 68 and is received and frictionally retained in theend 94 of thetube 24. - The bearings 58, 84 are of a suitable material such as sintered bronze. To insure adequate lubrication of the bearings 56, 57, 84, 85, and particularly the rear bearings, they are impregnated with lubricant and a small quantity of a synthetic high temperature lubricating oil is also disposed in the
chamber 14. - To provide a longer life in service, relatively little clearance is provided between each
rod - Movement of the
first rod 16 to its extended position is limited by a positive stop 96 provided by cooperation of an end face 98 of therear housing 44 with acomplementary shoulder 100 on the head 20 of thefirst rod 16. Movement of thesecond rod 18 to its extended position is limited by apositive stop 102 provided by engagement of aconical surface 104 on theback face 106 of therear housing 76 with a complementary surface on thehead 22 of thesecond rod 18. - While the
rod seals continuous sealing ring 110 which, as shown in Fig. 2, in a relaxed or unflexed state, has in cross section a generally C-shape with side walls or arms 112, the central portions of which are urged into contact with their adjacent rod and housing surfaces by a circumferentially continuousmetal spring element 114 received in thering 110. Preferably, thering 110 is made of a low friction and highly wear resistant elastomeric material such as an ultra high molecular weight polyethylene. - Preferably, the free edges of the arms 112 have generally right angular surfaces defining a sharp peripheral edge or
lip 116. In assembly, when pressurized gas is admitted to thechamber 14, as shown in Fig. 3, the arms 112 are extended and forced along with thelips 116 into firm sealing engagement with the adjacent surfaces of therods housings ring 110 to engage with and conform to the peripheral surfaces of the cavity in which it is received. Appropriate seals as thus far described are disclosed in U.S. Patent 4,508,356 and commercially available from Tetraflour, Inc., 2051 E. Maple Avenue, EI Segundo, California 90245, under the tradename "TETRALENE MULTI-FLEX SEALS". - It has been found that further improved sealing performance and a significantly decreased tendency for the seal to cock or turn in the groove and thereby leak can be achieved if the outer wall or arm 118 of the
ring 110 is substantially thicker than its inner wall or arm 120. Preferably, as illustrated in the drawings, the radial thickness of the outer wall 118 is about 110% to 250% times the radial thickness of the inner wall 120. - The interior of each seal continuously communicates with the
chamber 14 through one ormore passages 124, which are preferably formed byinterconnected grooves 126 in the rear bearings 56, 84. Preferably,grooves 126 extend radially across the opposed end faces 128 of each rear bearing 56, 84 and are interconnected by agroove 126 extending axially across the outerperipheral surface 130 of each bearing 56, 84. Preferably, there are two or three sets of thesegrooves 126 circumferentially spaced about each bearing 56, 84. To prevent each rear bearing 56, 84 from being moved axially in itsrear housing seal passages 124 also substantially equalize the pressure of gas acting on the opposed end faces 128 of each bearing 56, 84. During charging and use of thegas cylinder 12, there are substantial gas pressure spikes or variations which without thesepassages 124 would produce a substantial difference in the pressure of the gas acting on opposed end faces 128 of the bearings 56, 84 which would move or shift the bearings 56, 84 axially in theirhousings - This bearing, seal and housing construction permits and facilitates the use of close tolerances and even interference fits between the bearings and housing members. The housing member is not required to move axially to compress and radially expand the seal. Elimination of this movement and use of close tolerances substantially reduces wear on the component parts and greatly extends the useful service life of the gas spring. Moreover, these close tolerances in conjunction with lubrication of the parts further enhances sealing and minimizes leakage of pressurized gas from the chamber.
- In use, the chamber is precharged with a compressed gas, such as nitrogen, to a relatively high internal pressure such as 13,79 MPa (2000 PSI). As shown in the force versus displacement curve of Fig. 4, a relatively small force is required to initially retract the
first rod 16 and this force increases only modestly as thefirst rod 16 is retracted, such as by advancement of the die plate, until the plate also bears on thesecond rod 18. This relatively low force for displacement of thefirst rod 16 is due to the relatively small area of its head 20 and the fact that the movement of thefirst rod 16 and head 20 only moderately compresses the gas in thechamber 14 and thereby only moderately increases the force required to continue to move therod 16 toward its retracted position. However, as indicated in Fig. 4, when the plate bears on thesecond rod 18 the total force required to simultaneously displace bothrods second rod 18 is due to the gas in thechamber 14 acting on the area of thesecond head 22 and the rapid increase of the force required to continue moving bothrods cylinder 12 by bothheads 20, 22 androds - Fig. 5 illustrates a modified
gas spring 134 which is the same as the two-stage gas spring 10 except that is has asingle rod 136 with aseal 138. Thisspring 134 illustrates application of the seal, bearing housing assembly 140 to gas springs having asingle rod 136 andhead 142. - In testing gas springs embodying this invention, and particularly two-rod springs, they have been found to operate at a substantially lower temperature and with substantially less wear on the rod. Indeed, two-rod gas springs embodying this invention have been tested for more than 1,000,000 substantially continuous cycles without any detected wear. In contrast, prior gas springs have failed after as few as 5,000 continuous cycles. In these two-rod gas springs, the first rod was moved toward its retracted position from 0 to 7,6 cm (0 to 3") by application of a force to its free end which increased generally linearly from about 2744,6 N to 3073,7 N (617 Ibs. to 691 lbs. ) and then both rods were moved simultaneously and additional 2,54 cm (1 ") by application of a force to their free ends which increased linearly from about 27,17 kN to 43,67 kN (6108 lbs. to 9816 lbs. ). In contrast, in comparably sized springs with a cylinder of the same diameter and length and a single rod and head like that of Fig. 5, the rod moved towards its retracted position from 0 to 10,16 cm (0 to 4") by application of a force to its free end which increased generally linearly from 27,17 kN to 43,23 kN (6108 lbs. to 9719 Ibs. ).
Claims (18)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US07/542,156 US5129635A (en) | 1990-06-21 | 1990-06-21 | Gas spring with c-shaped seal |
US542156 | 1990-06-21 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0464386A1 true EP0464386A1 (en) | 1992-01-08 |
EP0464386B1 EP0464386B1 (en) | 1996-09-18 |
Family
ID=24162578
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP91109215A Expired - Lifetime EP0464386B1 (en) | 1990-06-21 | 1991-06-06 | Gas spring |
Country Status (6)
Country | Link |
---|---|
US (1) | US5129635A (en) |
EP (1) | EP0464386B1 (en) |
JP (1) | JP3050641B2 (en) |
CA (1) | CA2035066C (en) |
DE (1) | DE69122180T2 (en) |
ES (1) | ES2093048T3 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES2221533A1 (en) * | 2002-07-26 | 2004-12-16 | Manuel Carcare Gimeno | Variable suspension cylinder for vehicle, has two telescopic pistons provided such that one of telescopic pistons is operated when vehicle is idle, and two telescopic pistons are operated when vehicle is fully-loaded |
ES2221514A1 (en) * | 2002-01-29 | 2004-12-16 | Manuel Carcare Gimeno | Oleo-pneumatic suspension cylinder for use in vehicle, has elastic element provided inside gas chamber, and two concentric telescopic pistons provided on outer jacket of hydraulic fluid accumulator |
ES2222113A1 (en) * | 2004-10-27 | 2005-01-16 | Manuel Carcare Gimeno | Oleo-pneumatic suspension device, has elastic part i.e. spring, connected between two points of two telescopic plungers by hydraulic device |
EP1437523A3 (en) * | 2003-01-09 | 2005-04-13 | Delphi Technologies, Inc. | Floating rod guide for monotube strut |
EP2037148A3 (en) * | 2007-09-13 | 2013-11-06 | Dadco, Inc. | Gas spring with guide |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5437436A (en) * | 1993-08-20 | 1995-08-01 | Ni-Tech, Inc. | Stand-alone gas spring |
US5344125A (en) * | 1993-09-17 | 1994-09-06 | Diebolt International, Inc. | Gas spring with filler valve |
US5549281A (en) * | 1994-01-25 | 1996-08-27 | Hall; G. Gordon | Liquid spring for punch press |
DE4436028A1 (en) * | 1994-10-08 | 1996-04-11 | Burkhard Oest | Gas pressure spring |
DE19545601C1 (en) * | 1995-12-07 | 1997-05-07 | Festo Kg | Suspension unit for road and rail vehicles |
US6003848A (en) * | 1997-07-01 | 1999-12-21 | Diebolt International, Inc. | Compact gas spring |
US6322059B1 (en) | 1998-07-23 | 2001-11-27 | Barnes Group Inc. | Low contact force spring |
JP3850663B2 (en) | 1998-07-23 | 2006-11-29 | テレダイン・インダストリーズ・インコーポレーテッド | Low contact force spring |
US6634862B2 (en) | 2000-09-15 | 2003-10-21 | General Dynamics Advanced Information Systems, Inc. | Hydraulic actuator |
US6340153B1 (en) | 2000-11-02 | 2002-01-22 | General Dynamics Advanced Technology Systems, Inc. | Shock and acoustic mount |
US7070028B2 (en) * | 2001-02-07 | 2006-07-04 | Tenneco Automotive Operating Company Inc. | Frequency dependent damper |
JP2006083837A (en) * | 2004-08-19 | 2006-03-30 | Tgk Co Ltd | Variable displacement compressor control valve |
US20160091046A1 (en) * | 2013-04-10 | 2016-03-31 | Magneti Marelli Cofap Fabricadora De Pecas LTDA. | Hydraulic shock absorber for suspension system and corresponding improved hydraulic stop |
EP2926920A1 (en) * | 2014-04-01 | 2015-10-07 | Gräbener Pressensysteme GmbH & Co. KG | Pressing device for processing a workpiece |
ES2947990T3 (en) * | 2020-04-26 | 2023-08-25 | Ningbo Kasico Shock Absorber Mft Co Ltd | Self-variable force hydraulic shock absorber |
CN114603764A (en) * | 2022-03-11 | 2022-06-10 | 河北振顺机械有限公司 | Processing equipment for producing rubber hammer |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1394560A (en) * | 1964-05-06 | 1965-04-02 | Bennes Samson | Device for simplified assembly of the means for leaktight guidance of the telescopic elements of cylinders |
FR2247649A1 (en) * | 1973-10-12 | 1975-05-09 | Bilstein August | |
DE2816761A1 (en) * | 1978-04-18 | 1979-10-31 | Fritz R Stolberg | Telescopic tube pneumatic spring arrangement - has one or more stages, and can be partially filled with liq. |
GB2057088A (en) * | 1979-07-17 | 1981-03-25 | Profil Verbindungstechnik Gmbh | Impact damper for reducing the noise of machines such as stamping machines |
GB2060814A (en) * | 1979-10-17 | 1981-05-07 | Perlini R | Fluid suspension unit with varying spring rate |
DE3130760A1 (en) * | 1981-08-04 | 1983-02-24 | Robert Bosch Gmbh, 7000 Stuttgart | Sealing arrangement |
US4508356A (en) * | 1984-06-06 | 1985-04-02 | Robert Janian | Modified C-shaped mechanical spring seal |
FR2579282A1 (en) * | 1985-03-20 | 1986-09-26 | Quiri Cie Sa Usines | Improved sealing assembly for gas springs and the like |
US4792128A (en) * | 1988-03-08 | 1988-12-20 | Power Components, Inc. | No grow gas spring |
US4838527A (en) * | 1987-03-03 | 1989-06-13 | Power Components, Inc. | Convertible gas spring |
GB2237095A (en) * | 1989-10-19 | 1991-04-24 | Quiri & Cie Usines | Gas compression device |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1288937A (en) * | 1917-05-05 | 1918-12-24 | Frederick H Leinweber | Landing-gear for airships. |
GB906848A (en) * | 1960-12-30 | 1962-09-26 | Flugzeugwerke Dresden Veb | A shock absorbing strut |
US3797366A (en) * | 1972-07-14 | 1974-03-19 | Vetco Offshore Ind Inc | Telescopic hydraulic decelerator |
SU683966A1 (en) * | 1977-08-08 | 1979-09-05 | Государственное Конструкторское Бюро Коксохимического Машиностроения "Гипрококса" | Rotary lift table of package-forming machine |
JPS601435A (en) * | 1983-06-17 | 1985-01-07 | Kenji Ogaki | Hydraulic buffer device for telescopic cylinder |
IT208341Z2 (en) * | 1986-11-10 | 1988-05-28 | Fiat Auto Spa | DAMPING DEVICE FOR SUSPENSION OF A VEHICLE |
FR2616503B1 (en) * | 1987-06-11 | 1992-07-10 | Ferco Int Usine Ferrures | DOUBLE ACTION SHOCK ABSORBER CAUSING LAMINATION OF A FLUID ON THE PASSAGE OF A THREAD |
-
1990
- 1990-06-21 US US07/542,156 patent/US5129635A/en not_active Expired - Lifetime
-
1991
- 1991-01-28 CA CA002035066A patent/CA2035066C/en not_active Expired - Fee Related
- 1991-06-06 EP EP91109215A patent/EP0464386B1/en not_active Expired - Lifetime
- 1991-06-06 DE DE69122180T patent/DE69122180T2/en not_active Expired - Fee Related
- 1991-06-06 ES ES91109215T patent/ES2093048T3/en not_active Expired - Lifetime
- 1991-06-21 JP JP3150258A patent/JP3050641B2/en not_active Expired - Fee Related
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1394560A (en) * | 1964-05-06 | 1965-04-02 | Bennes Samson | Device for simplified assembly of the means for leaktight guidance of the telescopic elements of cylinders |
FR2247649A1 (en) * | 1973-10-12 | 1975-05-09 | Bilstein August | |
DE2816761A1 (en) * | 1978-04-18 | 1979-10-31 | Fritz R Stolberg | Telescopic tube pneumatic spring arrangement - has one or more stages, and can be partially filled with liq. |
GB2057088A (en) * | 1979-07-17 | 1981-03-25 | Profil Verbindungstechnik Gmbh | Impact damper for reducing the noise of machines such as stamping machines |
GB2060814A (en) * | 1979-10-17 | 1981-05-07 | Perlini R | Fluid suspension unit with varying spring rate |
DE3130760A1 (en) * | 1981-08-04 | 1983-02-24 | Robert Bosch Gmbh, 7000 Stuttgart | Sealing arrangement |
US4508356A (en) * | 1984-06-06 | 1985-04-02 | Robert Janian | Modified C-shaped mechanical spring seal |
FR2579282A1 (en) * | 1985-03-20 | 1986-09-26 | Quiri Cie Sa Usines | Improved sealing assembly for gas springs and the like |
US4838527A (en) * | 1987-03-03 | 1989-06-13 | Power Components, Inc. | Convertible gas spring |
US4792128A (en) * | 1988-03-08 | 1988-12-20 | Power Components, Inc. | No grow gas spring |
GB2237095A (en) * | 1989-10-19 | 1991-04-24 | Quiri & Cie Usines | Gas compression device |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ES2221514A1 (en) * | 2002-01-29 | 2004-12-16 | Manuel Carcare Gimeno | Oleo-pneumatic suspension cylinder for use in vehicle, has elastic element provided inside gas chamber, and two concentric telescopic pistons provided on outer jacket of hydraulic fluid accumulator |
ES2221533A1 (en) * | 2002-07-26 | 2004-12-16 | Manuel Carcare Gimeno | Variable suspension cylinder for vehicle, has two telescopic pistons provided such that one of telescopic pistons is operated when vehicle is idle, and two telescopic pistons are operated when vehicle is fully-loaded |
EP1437523A3 (en) * | 2003-01-09 | 2005-04-13 | Delphi Technologies, Inc. | Floating rod guide for monotube strut |
ES2222113A1 (en) * | 2004-10-27 | 2005-01-16 | Manuel Carcare Gimeno | Oleo-pneumatic suspension device, has elastic part i.e. spring, connected between two points of two telescopic plungers by hydraulic device |
EP2037148A3 (en) * | 2007-09-13 | 2013-11-06 | Dadco, Inc. | Gas spring with guide |
Also Published As
Publication number | Publication date |
---|---|
JPH04231743A (en) | 1992-08-20 |
JP3050641B2 (en) | 2000-06-12 |
CA2035066C (en) | 1999-04-06 |
US5129635A (en) | 1992-07-14 |
ES2093048T3 (en) | 1996-12-16 |
DE69122180T2 (en) | 1997-04-17 |
EP0464386B1 (en) | 1996-09-18 |
DE69122180D1 (en) | 1996-10-24 |
CA2035066A1 (en) | 1991-12-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5129635A (en) | Gas spring with c-shaped seal | |
EP0922169B1 (en) | Compact gas spring | |
US4792128A (en) | No grow gas spring | |
US3653670A (en) | Spring-loaded seal with symmetrical cross section | |
US4932313A (en) | Air bearing piston and cylinder assembly | |
US6290235B1 (en) | Sealing system for a reciprocating shaft | |
EP1628037B1 (en) | Low impact gas spring | |
US4893823A (en) | Seal assembly | |
EP1441145B1 (en) | Low contact force spring | |
CA2639191C (en) | Gas spring with guide | |
US5291974A (en) | High pressure self-contained gas spring or die cylinder and sealing arrangement therefor | |
EP1626194B1 (en) | Low impact gas spring | |
US5823513A (en) | Delay return gas spring | |
US6199838B1 (en) | Gas spring filler valve | |
WO1998051427A1 (en) | Sealing unit for hydroforming apparatus | |
US3336842A (en) | Hydraulic actuator | |
GB2333332A (en) | Improved seal for gas springs and the like | |
US5220820A (en) | Apparatus and method for cushioning movement of a member in a press | |
CA1286698C (en) | Die spring construction | |
US4632405A (en) | Device for forcing piston ring radially outwardly | |
JP3661254B2 (en) | Combined seal for bearings | |
IL47525A (en) | High pressure seal | |
JPS63210469A (en) | Seal device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE ES FR GB IT SE |
|
17P | Request for examination filed |
Effective date: 19920702 |
|
17Q | First examination report despatched |
Effective date: 19930927 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
ITF | It: translation for a ep patent filed |
Owner name: DE DOMINICIS & MAYER S.R.L. |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE ES FR GB IT SE |
|
REF | Corresponds to: |
Ref document number: 69122180 Country of ref document: DE Date of ref document: 19961024 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2093048 Country of ref document: ES Kind code of ref document: T3 |
|
ET | Fr: translation filed |
Free format text: CORRECTIONS |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20040602 Year of fee payment: 14 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20050606 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20050617 Year of fee payment: 15 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 20050621 Year of fee payment: 15 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: ES Payment date: 20050708 Year of fee payment: 15 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20050606 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20060607 Ref country code: ES Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20060607 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20060630 Year of fee payment: 16 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20060731 Year of fee payment: 16 |
|
EUG | Se: european patent has lapsed | ||
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20070228 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 20060607 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20060630 Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20080101 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20070606 |